JP2021028129A - Image formation device - Google Patents

Abstract

To provide an image formation device which can suppress conveyance deviation of a transfer medium with simple configuration without use of a special component.SOLUTION: An image formation device primarily transfers an ink image onto a moving transfer film 601, and secondarily transfers the ink image to a recording medium to form an image, and winds the transfer film after secondary transfer of the ink image. In this device, a control part, which controls image formation, transfers an ink on an outer side of an image formation area of the transfer film and along direction of movement of the transfer film to form a dummy image when primarily transferring the ink image onto the image formation area of the transfer film.SELECTED DRAWING: Figure 5

Description

The present invention relates to an image forming apparatus that first transfers an ink image to a transfer medium such as a transfer film and then secondarily transfers (retransfers) the ink image to a recording medium such as a card to form an image.

Some image forming devices that form an image on a small-sized recording medium such as a card form an image on the recording medium by an indirect printing method by using an ink ribbon and a transfer film. Specifically, the ink ribbon and the transfer film were overlapped and conveyed, and the ink image was first transferred from the ink ribbon to the transfer film by heating according to the image signal by the thermal head, and then transferred to the transfer film. An image is formed by secondary transfer (retransfer) of an ink image to a recording medium.

In the image forming apparatus using the transfer film as described above, the transfer film after the ink image is transferred to the recording medium is wound around the winding shaft. At this time, the transfer film to be wound may be offset on the winding shaft, so-called film deviation may occur. If this film shift occurs, the transfer film on the upstream side before being wound may be wrinkled, or the transferred ink image may be displaced and the ink image transferred to the card may be chipped.

The transfer film shift occurs when the winding diameter is different on both sides of the winding shaft in the width direction, and the transfer film shifts from the larger winding diameter side to the smaller winding diameter side. When printing on a card or the like, so-called borderless printing may be performed. When printing without borders, an image is formed on the transfer film one size larger than the card size, and the transfer film is transferred. It prevents image loss at the edges due to misalignment of the card. In such an image forming apparatus for borderless printing, the ink of the portion larger than the card size remains without being transferred on the transfer film after the ink image is transferred to the card. Here, there is a case where borderless printing is performed on one end side in the width direction of the card and borderless printing is not performed on the other end side. When this transfer film is wound as it is, the thickness of the remaining ink on one end side is laminated, and the film winding outer diameter is adjusted to the part with the remaining ink on the one end side and the part without the remaining ink on the other end side. There is a difference and the film is closer to the film.

In order to suppress the film shift, a configuration has been proposed in which the parallelism in the transport direction of the film to be transported is detected and the angle of the take-up shaft is changed according to the film shift state (Patent Document 1). That is, the take-up shaft is configured so that the angle can be changed with respect to the film transport direction, and the film transport misalignment is corrected by changing the angle of the take-up shaft arranged in the direction orthogonal to the film transport direction. , The film is suppressed.

Japanese Unexamined Patent Publication No. 2018-83332

However, in the configuration in which the angle of the winding shaft for winding the film is adjusted as described above in order to suppress the film deviation, the detection means for detecting the film deviation and the winding shaft can be changed in angle. At the same time, a drive configuration for changing the angle is also required. As a result, the device configuration becomes complicated and the cost increases.

The present invention solves the above problems, and an object of the present invention is to provide an image forming apparatus capable of suppressing the deviation of a transfer medium with a simple structure without using a special member.

A typical configuration according to the present invention for achieving the above object is to first transfer an ink image to a transfer medium and then secondarily transfer the ink image transferred to the transfer medium to a recording medium to form an image. In an image forming apparatus that transports and winds up the transfer medium after the secondary transfer, when the ink image is first transferred to the image forming region of the transfer medium, the image forming region of the transfer medium is used. The feature is that the ink is primarily transferred to the outside of the transfer region to be transferred to the recording medium to form a dummy image that is not secondarily transferred to the recording medium.

According to the present invention, it is possible to suppress the deviation of the transfer medium with a simple structure without using a special member.

Overall configuration diagram of the image forming apparatus according to the embodiment of the present invention Cross-sectional view of the transfer film after primary transfer and secondary transfer Sectional view of the transfer film after the primary transfer and the secondary transfer according to the embodiment. Explanatory drawing showing an example of forming a dummy image Explanatory drawing which shows formation area of dummy image Control block diagram Flowchart showing the procedure for forming a dummy image A flowchart showing a procedure for forming a dummy image according to the second embodiment. Explanatory drawing which shows the formation example of the dummy image which concerns on 2nd Embodiment Sectional drawing which shows the state which wound the transfer film which formed the dummy image which concerns on 2nd Embodiment

Next, an image forming apparatus according to a preferred embodiment of the present invention will be described with reference to the drawings.

[First Embodiment]
<Overall configuration of image forming device>
FIG. 1 is an explanatory diagram of an overall configuration of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus of FIG. 1 forms images such as characters, photographs, and marks on ID cards for various certifications, credit cards for commercial transactions, and the like. Therefore, the image forming apparatus includes a card supply unit 100, a rotating unit 200, and an image forming unit 300.

The card supply unit 100 is a card cassette 101 that is removable from the main body of the device and stores the card C, which is a recording medium. A plurality of cards C are arranged and stored in the card cassette 101 in a standing position, and are urged by the support member 102 from the left end to the right end of FIG. A separation opening 103 through which one card can pass is provided on the lower surface of the right end of the card cassette 101, and is supplied into the device from the card C in the front row by the rotation of the pickup roller 104.

The card C sent from the card cassette 101 is sent to the rotating unit 200. As shown in FIG. 1, the rotating unit 200 is provided so that two roller pairs 201 and 202 arranged in the front-rear direction at a distance from each other are axially supported by the unit frame 203 and can rotate in the forward and reverse directions. Then, the unit frame 203 is pivotally supported by the apparatus main body so as to be rotatable forward and reverse, thereby changing the transport direction of the card C sandwiched by the roller pairs 201 and 202. Although these rotation drive mechanisms are not shown, for example, one pulse motor is configured to rotate and drive the unit frame 203 and the rollers 201 and 202 by switching the rotation with a clutch.

Therefore, the cards C prepared in the card cassette 101 are fed out by the pickup roller 104, separated one by one when passing through the separation opening 103 having an opening amount equivalent to one card C, and sent to the rotary unit 200 on the downstream side. Be done. Then, the rotating unit 200 carries the card C into the unit by the rollers 201 and 202, and deflects the posture of the card C in a predetermined direction with the card C nipped by the rollers 201 and 202. When the card C is sent to the image forming unit 300, the unit frame 203 is rotated so that the card C nipped by the roller pairs 201 and 202 is horizontal. Then, in that state, the rollers 201 and 202 are driven to transport the card C to the image forming unit 300 via the transport path 400 provided with the transport rollers 401 and 402 and the like.

The image forming unit 300 primaryly transfers an ink image to a transfer film as a transfer medium using a sublimation type ink ribbon, and secondarily transfers the ink image to a card C as a recording medium to form an image. Therefore, the image forming unit 300 includes an ink ribbon transfer unit 500, a transfer film transfer unit 600, a primary transfer unit including a thermal head 701 and a platen roller 702, and a secondary transfer unit including a heat roller 703 and a support roller 704. have.

As shown in FIG. 1, the ink ribbon 501 is housed in the ink ribbon cassette 502, and the transfer film 601 is housed in the transfer film cassette 602. At the time of image formation, the ink ribbon 501 and the transfer film 601 were fed out as described later, and were melted by heating the ink ribbon 501 in close contact with the transfer film 601 from the thermal head 701 according to the image signal in the primary transfer portion. The ink image is first transferred to the transfer film 601. Then, the card C, which is a recording medium conveyed in the secondary transfer unit, and the transfer film 601 to which the ink image is transferred are conveyed so as to overlap each other, and the heat roller 703 is heated while being pressed against the transfer film 601 to obtain ink. The image is secondarily transferred to the card C to form an image. Then, the card C after the ink image is transferred is discharged to the discharge unit 800.

As shown in FIG. 1, the transport configuration of the ink ribbon 501 is such that an unused ink ribbon 501 is wound around the supply shaft 503 and a used ink ribbon 501 is wound around the winding shaft 504. Then, the supply shaft 503 and the take-up shaft 504 are rotationally driven by the drive units MR1 and MR2, respectively.

At the time of primary transfer, the unused ink ribbon of the supply shaft 503 is fed to the primary transfer unit where the thermal head 701 is located by rotationally driving the drive units MR1 and MR2. The ink ribbon after printing the image information on the transfer film 601 is wound around the take-up shaft 504 by the rotational drive of the drive units MR1 and MR2.

Similar to the case of the ink ribbon 501, the transfer film 601 is wound with an unused transfer film 601 around the supply shaft 604, and a used transfer film 601 is wound around the take-up shaft 603. .. The supply shaft 604 and the take-up shaft 603 are rotationally driven by the drive units MR4 and MR3, respectively.

At the time of primary transfer, the unused transfer film 601 is fed from the supply shaft 604 to the primary transfer unit by rotational driving of the drive units MR3 and MR4 and the transfer film transfer roller 605. In the primary transfer section, the transfer film 601 to which the ink image is first transferred is conveyed to the secondary transfer section, and the ink image on the surface of the transfer film is secondarily transferred (retransferred) to the card C by the heating and pressurization control of the heat roller 703. ). Then, the used transfer film 601 on which the ink image is secondarily transferred is wound around the take-up shaft 603.

<Proximity of transfer film>
The image forming apparatus of the present embodiment has a borderless recording mode for performing borderless printing that extends beyond the image forming region to form an ink image when the ink image is first transferred to the image forming region of the transfer film 601. doing. Here, with reference to FIG. 2, a mechanism in which film deviation is likely to occur when borderless printing is performed with a conventional image forming apparatus will be described. FIG. 2 is a schematic cross-sectional view of the transfer film for explaining the case where borderless printing is performed on only one side surface with respect to the transport direction (movement direction) of the transfer film.

FIG. 2A shows the cross-sectional structure of the transfer film 601. An image is formed on the base material 601a formed of a resin material such as PET by a release layer 601b that is peeled off from the transfer film 601 to the card C during the secondary transfer, and an ink ribbon 501 and a thermal head 701 during the primary transfer. It is formed of an intermediate layer 601c having a role of disconnecting the image receiving layer 601d, the peeling layer 601b, and the image receiving layer 601d.

FIG. 2B is a cross-sectional view of the transfer film 601 when the ink image is transferred by the primary transfer. Since the ink image is formed on the surface of the transfer film by the ink ribbon 501 and the thermal head 701, the ink deposit layer 501a is formed on the image receiving layer 601d of the transfer film 601.

FIG. 2C is a cross-sectional view of the transfer film 601 after the secondary transfer. A region corresponding to the width of the card C on which the ink image is secondarily transferred is peeled from the release layer 601b of the transfer film 601.

Here, borderless printing is performed only on one end of the transport direction. When the print image transmitted / received from the operation unit to the control unit is borderless printing, a margin should be provided with respect to the width of the card C so as not to leave a margin at the edge of the card C which is a recording medium. The printed image is enlarged and the primary transfer is performed on the transfer film 601. In this embodiment, the extra length is about 0.5 mm.

As shown in FIG. 2C, when only one end of the transfer direction is borderless printed, the ink deposit layer 501a is placed on the transfer film 601 even after the secondary transfer by the marginless printing surplus length. It will remain. Therefore, the surface of the used transfer film 601 after the secondary transfer is thicker only in the region of the ink deposition layer 501a where the side with the borderless printing remains as compared with the other side without the borderless printing, and the surface of the transfer film is in the transport direction. The height is uneven on the left and right.

When borderless printing in the above state is continuously performed, as shown in FIG. 2C, a transfer film thicker by the ink deposit layer on one side in the transport direction is wound around the take-up shaft 604. Since the thickness continues to increase on one side in the overlapping process, the transfer film 601 flows from the thick side to the thin side, causing the transfer film to be closer to the film.

<Structure to prevent the transfer film from leaning>
In order to suppress the film shift due to the non-uniformity of the film winding diameter, the image forming apparatus of the present embodiment has an image forming region on the card C when the ink image is first transferred to the image forming region of the transfer film 601. The ink is transferred along the transport direction of the transfer film 601 to form a dummy image.

It is important to keep the surface height of the transfer film 601 equal in order to prevent the transfer film 601 from leaning. Therefore, if the image to be printed on the card is a borderless image on the side of the transfer film 601 along the transport direction, that is, at the end of the transfer film C in the direction orthogonal to the transport direction (card width direction), the image is borderless. When the printing is borderless printing on only one side in the width direction, for example, FIG. 3A and FIG. 4, only the left side in the card width direction, the borderless image is transferred to the left side with a margin. The dummy image D is transferred to the outside of the image forming region on the right side in the width direction, which is the side opposite to the side where the borderless image is formed.

The dummy image D transfers a linear ink image outside the image forming region E, which is the size of the card C, along the transport direction of the transfer film 601. In the present embodiment, the extra length W1 of the borderless image is 0.5 mm, and the width W2 of the dummy image is 1.0 mm.

As shown in FIG. 3B, an image forming region is formed on the transfer film 601 after the borderless image obtained by transferring the ink image to the transfer film 601 as described above is transferred to the card C in the secondary transfer unit. The ink deposit layer for the extra length of the borderless image remains on the left side in the transfer film transport direction of E (FIG. 4), and the ink deposit layer of the dummy image D remains on the right side. Therefore, the height uniformity can be maintained on the left and right with respect to the transport direction of the transfer film 601. As a result, even in a printed image in which a borderless image is continuously formed on only one side with respect to the transport direction of the transfer film 601, it is possible to prevent the transfer film from being displaced on the take-up shaft after the secondary transfer.

FIG. 5 illustrates a region where the dummy image D is formed in the present embodiment. The effective recording width of the thermal head has an extra length with respect to the size (image forming region) width of the card C which is a recording medium. Then, in the present embodiment, the dummy image D can be formed in a region that does not affect the printed image by using effective pixels that are further outside the extra length region when performing borderless printing. As the dummy image D, for example, by forming the same image as the image formed in the borderless print extra length region in the dummy image print region, the surface height of the transfer film can be kept equal on the left and right.

<Control of transfer film deviation>
Next, the control of suppressing the deviation of the transfer film in the present embodiment will be described.

As shown in the control block diagram of FIG. 6, the drive control of the image forming apparatus including the control of suppressing the deviation of the transfer film is controlled by the control unit 900 having the CPU 901, the ROM 902, and the RAM 903. The CPU 901 acquires an operation signal, an image signal, a detection signal of a recording medium, etc. from the operation unit 801 and drives the card supply unit 100 and the rotation unit 200 based on the data stored in the ROM 902 and the RAM 903 to drive the card C. The image forming unit 300, the ink ribbon conveying unit 500, and the transfer film conveying unit 600 are driven to transfer the ink image to the card C via the transfer film 601.

FIG. 7 is a flowchart showing a procedure for controlling the deviation of the transfer film in the case of borderless printing.

When the image formation is started, the CPU 901 of the control unit 900 acquires a printed image from the printer driver (S1), and the image to be printed on the card C is on the side of the transfer film 601 along the transport direction, that is, the end portion in the card width direction. It is determined whether or not the image is borderless (S2). When the printed image is the borderless printing, it is determined whether or not the borderless printing is borderless printing on only one side in the width direction, for example, the left side (S3). In the case of borderless printing on the left side only, when the ink image is first transferred to the transfer film 601 at the primary transfer unit, the borderless image is transferred to the left side with a margin as shown in FIG. , The dummy image D is transferred to the outside of the image forming region on the right side in the width direction opposite to the side on which the borderless image is formed (S4).

In step S3, when the borderless printing is not the borderless printing only on the left side, it is determined whether or not the borderless printing is the other side in the width direction, that is, the borderless printing only on the right side (S5). In the case of borderless printing only on the right side, when the ink image is first transferred to the transfer film 601 in the primary transfer section, the borderless image is transferred to the right side with a margin and the borderless image is formed. The dummy image D is transferred to the outside of the image forming region on the left side in the width direction opposite to the side to be printed (S6).

As described above, in the case of borderless printing on only one side in the width direction, a dummy image D is formed outside the image forming area on the opposite side, the printed image is secondarily transferred to the card C (S7), and the remainder on one side. The transfer film 601 with the long ink deposit layer and the ink deposit layer of the dummy image remaining on the other side is wound around the take-up shaft 604 to finish printing (S8).

When the borderless printing is not limited to the right side in step S5, the borderless image printed on the card C is borderless printing formed on both the left and right sides in the width direction. In this case, since the ink deposit layer for the extra length remains on both the left and right sides of the transfer film 601 after the secondary transfer, the surface height of the transfer film is kept equal on the left and right even if the dummy image is not transferred. .. Therefore, in that case, the printed image is first transferred to the transfer film 601 (S9) without forming a dummy image, and the ink image is secondarily transferred to the card C at the secondary transfer unit to end the printing (S). S7, S8).

Further, in step S2, even when the printed image is not borderless printing, an extra length of ink deposit layer does not remain outside the image forming region of the transfer film, so the process proceeds to step S9 to form a dummy image D. The printed image is transferred to the transfer film 601 without any problem.

As described above, in the case of borderless printing on only one side in the width direction, by forming a dummy image D outside the image forming region on the opposite side at the same time as forming the borderless image, it is simple without using a special member. With the configuration, it is possible to eliminate the occurrence of deviation in the surface height of the transfer film 601 after the secondary transfer and suppress the deviation of the transfer film to be wound up.

[Second Embodiment]
In the first embodiment described above, an example is shown in which a dummy image D is formed outside the image forming region on the opposite side in the case of borderless printing on only one side in the width direction. In the present embodiment, when borderless printing is performed, dummy images D are formed on both outer sides of the image forming region in the width direction orthogonal to the conveying direction of the transfer film.

Specifically, as shown in the flowchart of FIG. 8, when printing is started, the CPU of the control unit acquires a printed image (S21), and the image to be printed on the card C follows the transport direction of the transfer film 601. It is determined whether or not the image is borderless on the side, that is, at the end in the width direction of the card (S22). When the printed image is borderless printing, the printed image is primarily transferred to the transfer film 601 and is on both sides in the width direction orthogonal to the transport direction of the transfer film 601 as shown in FIG. 9 outside the image forming region. The dummy image D is transferred (S23). Then, the primary transferred printed image is secondary transferred to the card C at the secondary transfer unit (S25), and the transfer film 601 after the ink image transfer is wound around the winding shaft 603.

On the other hand, in step S22, if the printed image is not a borderless image, the process proceeds to step S24 to primary transfer the printed image to the transfer film 601 and secondary transfer the ink image to the card C to end printing (S25). , S26).

As described above, when printing a borderless image, by forming dummy images on both sides in the width direction of the transfer film, as shown in FIG. 10, the transfer film 601 after the secondary transfer has both ends of the transfer film. The portion to which the dummy image D of the portion is transferred has the largest thickness. As a result, the wound transfer film 601 does not have a difference in the winding outer diameters at both ends, and the film can be prevented from shifting.

In the present embodiment, the dummy image D is formed when the borderless image is printed. However, even when the borderless image is not printed, the ink image is formed even if the dummy image is formed. As shown in FIG. 10, the thickness of the dummy image portion of the transfer film after the secondary transfer is the largest, and the thickness is the same on the left and right sides in the width direction, so that it is possible to prevent the film from shifting.

In the first and second embodiments described above, the length of the dummy image D in the film transport direction is set to be equal to or longer than that of the card C, but the length is not limited to this. For example, if the print area of the borderless image is half the length of the card C, the length of the dummy image D in the film transport direction may be half the length of the card C. By making the length of the dummy image D equal to the edgeless image length, the height of the surface of the transfer film 601 on the take-up axis can be kept the same, so that the transfer film 601 can be prevented from leaning. .. Therefore, by setting the length of the dummy image D to the same length according to the length of the print area of the borderless image, it is possible to prevent the transfer film from shifting.

In the first embodiment described above, the width W2 of the dummy image is 1.0 mm, but both the first and second embodiments are not limited to this. The width W2 of the dummy image may be wider than the extra length W1 of the borderless image. For example, the width W2 of the dummy image may be any number of millimeters as long as it is outside the transfer region to be transferred to the card C, which is a recording medium, and inside the effective recording width of the thermal head (see FIG. 5). ..

In the first embodiment described above, the color of the ink ribbon forming the dummy image D is not specified, but the color of the ink ribbon forming the borderless image or the same number of colors may be used to form the dummy image D. Just do it. Here, the normal ink ribbon 501 is provided with a plurality of colors of yellow layer (Y), magenta layer (M), cyan layer (C), and black layer (K) provided along the transport direction along the transport direction. A plurality of them are provided in succession. Therefore, if the borderless image uses yellow and magenta, the dummy image D may use yellow and magenta or cyan and black. This is because if the dummy image D is formed in this way, the thickness of the borderless image and the thickness of the dummy image D are equal on the winding shaft.

Further, in the second embodiment described above, the dummy image D is formed at both ends of the effective recording width of the thermal head, but the dummy image D has at least the same number of colors as or more than the number of colors of the ink ribbon forming the borderless image. You can use the number. When the dummy image D is formed in this way, the maximum thickness on the take-up axis is due to the region where the dummy image D is formed.

C ... Card D ... Dummy image E ... Image formation area 100 ... Card supply unit 101 ... Card cassette 200 ... Rotation unit 300 ... Image formation unit 400 ... Transfer path 501 ... Ink ribbon 501a ... Ink deposit layer 601 ... Transfer film 604 ... Supply Shaft 603 ... Winding shaft 701 ... Thermal head 702 ... Platen roller 703 ... Heat roller 704 ... Support roller 900 ... Control unit

Claims (6)

An image in which an ink image is first transferred to a transfer medium, the ink image transferred to the transfer medium is secondarily transferred to a recording medium to form an image, and the transfer medium after the secondary transfer is conveyed and wound up. In the forming device
When the ink image is primarily transferred to the image forming region of the transfer medium, the ink is primarily transferred to the outside of the transfer region which is the image forming region of the transfer medium and is transferred to the recording medium, and is transferred to the recording medium. An image forming apparatus characterized by forming a dummy image that is not secondarily transferred. It has a borderless recording mode in which when the ink image is primarily transferred to the image forming region of the transfer medium, the ink image is formed so as to protrude from the image forming region.
The image forming apparatus according to claim 1, wherein a dummy image is formed when the borderless recording mode is executed. The image forming apparatus according to claim 1 or 2, wherein the dummy image is formed on both outer sides of the image forming region in the transport direction of the transfer medium. The image forming apparatus according to claim 2, wherein the dummy image is formed along the moving direction on the side where the protruding ink image formed by the borderless recording mode is not formed. The image forming apparatus according to claim 2 or 4, wherein the dummy image is formed at the same time as the transfer of the ink image in the borderless recording mode. The image forming apparatus according to any one of claims 1 to 5, wherein the dummy image is an ink image continuous in the transport direction of the transfer medium.

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